From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id B402C221F13; Wed, 7 May 2025 11:59:37 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1746619179; cv=none; b=Cu0qVAdhye1Vw69xTkEpmqnJQP2+ZhZZYNBZsLlduskY2VbXxDeDI6I6NZKskKD7D8F22Ggk9QERrREbNyGhzBtVMFHV1gcc6fep/2eixhVrXVBUIISrcXHUGrQ2LtNxjPXdD01kZ1goGlZLBXLvQzapnyz59MnVNm2we/+pfMs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1746619179; c=relaxed/simple; bh=AI1HsAKecU9VCI5dP/B+WfjaQBA4Oer2ejuRed1fboI=; h=Message-ID:Date:MIME-Version:Subject:From:To:Cc:References: In-Reply-To:Content-Type; b=HoEAfldLJVgQA79o6We7H5X89z0zLyab0D+54LCK86ntbuBqBVZdwY+Ve99xBI7QvgCwG059AdIsVLYgCRVCi3dpo8qwlBeSRW3A6gK9q07p+IOIjGkOW/aeQ9rN9WMGaQ5UPGrLnHK1L3Aecll+gm98UsIBwGf97BoeHdTAk1s= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id AC905339; Wed, 7 May 2025 04:59:26 -0700 (PDT) Received: from [10.1.30.69] (Suzukis-MBP.cambridge.arm.com [10.1.30.69]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id BC54B3F5A1; Wed, 7 May 2025 04:59:34 -0700 (PDT) Message-ID: Date: Wed, 7 May 2025 12:59:33 +0100 Precedence: bulk X-Mailing-List: linux-arm-msm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v3 2/2] coresight: add coresight Trace Network On Chip driver Content-Language: en-GB From: Suzuki K Poulose To: Yuanfang Zhang , Mike Leach , James Clark , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Alexander Shishkin Cc: kernel@oss.qualcomm.com, linux-arm-msm@vger.kernel.org, coresight@lists.linaro.org, linux-arm-kernel@lists.infradead.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org References: <20250411-trace-noc-v3-0-1f19ddf7699b@quicinc.com> <20250411-trace-noc-v3-2-1f19ddf7699b@quicinc.com> <23d02991-3bc6-41e2-bb8b-a38786071c43@arm.com> <257fb0a5-7bf7-4a04-9f8d-d8759351584c@quicinc.com> <9b75b9d1-a9ed-46c9-9dba-8e3eb261dcc0@arm.com> <4a6a8bad-e5d9-4613-a839-5a21491ef7c4@quicinc.com> <069e920c-7023-4a6d-b1c6-dc87ac9d2360@arm.com> In-Reply-To: <069e920c-7023-4a6d-b1c6-dc87ac9d2360@arm.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit On 07/05/2025 09:52, Suzuki K Poulose wrote: > On 07/05/2025 05:26, Yuanfang Zhang wrote: >> >> >> On 5/6/2025 7:20 PM, Suzuki K Poulose wrote: >>> On 14/04/2025 10:16, Yuanfang Zhang wrote: >>>> >>>> >>>> On 4/11/2025 5:59 PM, Suzuki K Poulose wrote: >>>>> On 11/04/2025 09:57, Yuanfang Zhang wrote: >>>>>> Add a driver to support Coresight device Trace Network On Chip >>>>>> (TNOC), >>>>>> which is an integration hierarchy integrating functionalities of TPDA >>>>>> and funnels. It aggregates the trace and transports to coresight >>>>>> trace >>>>>> bus. >>>>>> >>>>>> Compared to current configuration, it has the following advantages: >>>>>> 1. Reduce wires between subsystems. >>>>>> 2. Continue cleaning the infrastructure. >>>>>> 3. Reduce Data overhead by transporting raw data from source to >>>>>> target. >>>>>> >>>>>>      +------------------------+ >>>>>> +-------------------------+ >>>>>>      | Video Subsystem        |                |Video >>>>>> Subsystem          | >>>>>>      |       +-------------+  |                | >>>>>> +------------+    | >>>>>>      |       | Video TPDM  |  |                |       | Video >>>>>> TPDM |    | >>>>>>      |       +-------------+  |                | >>>>>> +------------+    | >>>>>>      |            |           |                |              | >>>>>>           | >>>>>>      |            v           |                | >>>>>> v          | >>>>>>      |   +---------------+    |                | >>>>>> +-----------+    | >>>>>>      |   | Video funnel  |    |                |        |Video >>>>>> TNOC |    | >>>>>>      |   +---------------+    |                | >>>>>> +-----------+    | >>>>>>      +------------|-----------+ >>>>>> +------------|------------+ >>>>>>                   |                                         | >>>>>>                   v-----+                                   | >>>>>> +--------------------|---------+                         | >>>>>> |  Multimedia        v         |                         | >>>>>> |  Subsystem   +--------+      |                         | >>>>>> |              |  TPDA  |      |                         v >>>>>> |              +----|---+      |              +---------------------+ >>>>>> |                   |          |              |    Aggregator TNOC  | >>>>>> |                   |          |              +----------|----------+ >>>>>> |                   +--        |                         | >>>>>> |                     |        |                         | >>>>>> |                     |        |                         | >>>>>> |              +------v-----+  |                         | >>>>>> |              |  Funnel    |  |                         | >>>>>> |              +------------+  |                         | >>>>>> +----------------|-------------+                         | >>>>>>                     |                                       | >>>>>>                     v                                       v >>>>>>          +--------------------+ >>>>>> +------------------+ >>>>>>          |   Coresight Sink   |                    |  Coresight >>>>>> Sink  | >>>>>>          +--------------------+ >>>>>> +------------------+ >>>>> >>>>> If each NOC has TraceID, how do you reliably decode the trace ? >>>>> Is there a single NOC/TPDA in the path from Source to sink ? >>>> >>>> Not each TNOC has TraceID, there is only one TNOC has TraceID for >>>> one path >>>> from Source to sink. In the example, only the aggregator TNOC has >>>> traceID. >>>> Decode trace relying on TraceID + Inport number. >>>> It can has mutiple TNOC/TPDA in one path. >>> >>> So do we only describe the TNOCs that need traceId in the DT ? (e.g., >>> Aggregator TNOC above ?) How about Video TNOC ? Don't we allocate a >>> trace id for it by default, when it is described ? >>> >>> Suzuki >>> >> yes, now only describe the TNOCs which need traceID, Video TNOC is >> another type, it is interconnect TNOC which collects trace from >> subsystems >> and transfers Aggr TNOC, it doesn't have ATID. Its driver is different >> from this patch, I want to describe it when upstream its driver. So, if both are TNOC and there different types of them, how do you plan to identify, which is what ? And we also have a dt-bindings which simply says "coresight-tnoc". Isn't too generic if it is meant to be "aggregator" ? Suzuki > > Thanks! Please could you make sure to describe all of this when sending > out a patch in the cover letter ? > > Cheers > Suzuki > > >> >> Yuanfang >> >> >> >> >> >> >